Oil-based liquid refineries have many underground pipes for transporting the oil-based liquid. Gasoline service stations have underground pipes and tanks. Leaky pipes and tanks result in the oil-based liquid polluting the ground and ground water.
Solvents made from oil-based liquid are useful as cleaners. These solvents were often disposed of by pouring them on the ground which also results in pollution of the ground and ground water. Military bases are notorious for having disposed of solvents in this manner.
These subterranean oil-based liquid pollutants are often referred to as free products and they collect in what is known as fresh water sands. Some oil-based liquids are less dense, i.e., lighter, than water and float on the water surface. Other oil-based liquids are denser, i.e. heavier, than water and the water floats on the oil-based liquid.
It is difficult to clean up these subterranean oil-based liquids. Presently, a well is drilled into the ground to form a sump into which the oil-based liquid and water flow and from which the oil-based liquid is pumped to the surface. Often the water is pumped with the oil-based liquid, contaminating the oil-based liquid. Due to the cost of separating them, the oil-based liquid and water are either burned or buried which is expensive and results in a waste of the oil-based liquid--a nonrenewable resource.
Skimmers are known for removing sump oil-based liquid located near the earth's surface. The skimmers are inserted in a hole and have a downwardly extending belt that is externally supported by a rigid rod along the path the belt travels. The distance the belt extends down is fixed because the length of the rod is fixed and cannot be varied in response to variations in the oil-based liquid or water levels. When the water level rises so that the belt extends into the water, the amount of water contaminating the oil-based liquid increases. The contaminated oil-based liquid is burned or buried which results in a loss of a nonrenewable resource. Also, the need for the rod limits the distance the belt can extend down because as the distance increases the length and diameter of the rod must also increase to support the belt.
Oil-based liquid that is denser than water often flows to, and collects under, the water in a lagoon, pond or lake making it difficult to remove, especially when the water is very deep. The water interferes with the removal.
Oil-based liquids are also useful as cleaners in many manufacturing processes, such as metal manufacturing. For example, in aluminum manufacturing, water, coolant and a water-soluble oil-based liquid are used in a washing/cooling step for the hot aluminum. Impurities, e.g., magnesium oxide and aluminum, become emulsified in some of the oil-based liquid in this step. The resulting hot water, coolant, oil-based liquid and emulsion are collected in a sump where the emulsion separates out to the top.
The water, coolant and oil-based liquid are pumped from the sump and used again in the washing/cooling step with make-up water, coolant and oil-based liquid. The emulsion is preferably not used in the washing/cooling step. Rigid hoops of an allegedly emulsion absorbent material have been rotated through the emulsion in an attempt to remove it from the sump. Unfortunately, the hoops do not absorb the emulsion, due in part to the graphite-like nature of the emulsion, and are ineffective. Because the emulsion cannot be removed, the interface between the emulsion and the recyclable water, coolant and oil-based liquid is not visible through the emulsion. Excess make-up water, coolant and oil-based liquid must be used to avoid accidentally pumping the emulsion.
A method and apparatus that can vertically lift the oil-based liquid using a free hanging ribbon is highly desirable.